Efeito da temperatura na bioacumulação e eliminação do metilmercúrio em robalo (Dicentrarchus labrax)

• Author(s): Custódio, Ana Filipa Silva
• Date: 2014
• Persistent ID: http://hdl.handle.net/10400.5/8270
• Origin: Repositório da UTL
• Subject(s): climate change; temperature; methylmercury; bioaccumulation; sea bass
• Document Type: Master thesis
• Language: Portuguese
• Advisor(s): Marques, António Manuel Barros; Maulvault, Ana Luísa Marques Paixão de Carvalho; Martins, Maria Luísa Louro
• Contributor(s): Custódio, Ana Filipa Silva

Description

In this study the effects of seawater temperature increase expected in climate change in bioaccumulation of mercury (Hg) were studied in sea bass (Dicentrarchus labrax). The concentration of total mercury (total Hg) and methylmercury (MeHg) were determined in fish samples subjected to 28 days of exposure to a diet contaminated with MeHg, followed by 28 days of elimination (i.e. non contaminated diet). The results revealed that the highest concentrations of Hg were observed in sea bass maintained at higher temperature (22 ºC). Total Hg and MeHg concentrations increased during the exposure phase, starting from 0.10 and 0.08 mg kg-1, respectively, on day 0, and reaching 0.11 and 0.08 mg kg-1 in scenario 1, 1.47 and 1.23 mg kg-1 in scenario 2, and 1.78 and 1.50 mg kg-1 in scenario 3. During the elimination phase the concentrations of Hg remained stable in the three scenarios. In conclusion, this study revealed that sea bass exposed to higher temperatures bioaccumulate more Hg, thus being expected that climate change may exacerbate the risk associated with the consumption of seafood with identical characteristics to those of sea bass

Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia